Musical instruments use: 1. Sound selection devices to allow users to engage distinct pitches. 2. Wave propagation means to generate frequencies.
There are two great divisions of musical instruments; those termed fixed pitch, and those termed infinite pitch. The sound selection devices of infinite pitch instruments such as violins or trombones are able to provide an infinite number of pitch graduations from half step to adjacent half step. The fixed pitch instruments have sound selection devices that are crafted to provide only a finite collection of pitches, and these latter types are the primary focus of this instant art. Preferred embodiments of this invention typically provide a set collection of fixed pitches on operator command.
For musical instruments, wave propagation means may be further divided into two categories, pure acoustic and electricity enabled. Acoustic instruments employ resonating means for sound wave variations, and electricity enabled instruments utilize electronic generated means for sound wave variations. One typical example of electronic generated means is found in electronic keyboards, which can have virtual oscillators that are the object of command. These oscillators are activated, altered, amplified, and made audible by the electrical action of microprocessors.
The resonating means of acoustic embodiments fall into various categories according to the four general families of instrument involved:
1) Contained reed instruments. Soundholes are the selection devices, and the chambers containing the reeds are the resonating means. The operator selects between a plurality of soundholes to excite the contained reeds to the selected frequencies. An example is a harmonica. PA0 2) Column of air instruments. The valves or toneholes produce individual frequencies or elements in conjunction with the quality of air vibrations forced into the barrel. The valves or toneholes serve as selection devices, and the barrel containing the resonating air serves as the resonating means. The operator must choose which selection device to activate to produce a particular tone, whether by uncovering one particular tone hole, or by inserting or removing a length of tubing with a particular valve. PA0 3) Fretted stringed instruments. The frets serve as selection devices when acting in concert with the strings, since they are employed as length controlling means for the strings. The nut is a specialized fret when the string is used open. The neck of the instrument immobilizing and holding the strings at pitch is the resonating means. For instance with a guitar, the box at the bridge end is there to provide sound amplification, not resonance. PA0 4) Open stringed instruments. In this class the plurality of strings are not fretted, but in essence do have one static fret serving as a nut. Collectively the strings furnish a palette of frequencies for the operator to choose between. With a harp or piano example, the plurality of strings serve as the selection devices for tonality, and the frame provides the means for resonance. A misconception about pianos is that the sounding board is the means of resonance, when in fact it is mainly a means of amplifying the volume. A loose string is useless. It is the means that stretches and holds the string at pitch that actually allows it to resonate when struck.
Contained reed and column of air instruments can both be termed wind instruments. Also, other miscellaneous fixed pitch instruments such as xylophones exist and should not be ignored, but are not categorized herein.
Multitone instruments allow more than 12 pitches per octave. Most instruments of the current age are chromatic, not multitone. Some, such as harmonicas provide as few as 7 initial diatonic pitches per octave. Special embodiments are thus included to allow instruments with from 12 or less pitches per octave to have a plurality of the tone producing devices alter or exchange initial tones by operator selection to enable a multitone effect.
The invention does not lie with a particular type of tone selection device, of which there are many, but rather more as the defined relationships of a plurality of these devices acting in concert to provide a scale. A prior art instrument (configured to produce the 12 tone equal temperament politone) is incapable of producing bicameral tuned pitches by the distinct arrangement of its tone selection devices. Comparing a prior art acoustic guitar and the instant art acoustic guitar, the critical point to discern is that the interrelationships of the tone selection devices (frets) producing the prescribed frequencies are unique to both instruments, although the resonating means for both instruments are exactly the same.